Starting with 2.6, I'd like to showcase more game engine features in a supplied ruleset ("experimental" or similar), to let ruleset authors see what's available and enable playtesting. A lot of the time what holds me up is lack of art.

This is a bit different from usual art requests because it's not a request for a specific unit or whatever; the requirement is to demonstrate moddability, so to some extent the narrative details and exact behaviour can be left up to whatever people want to draw. We're not overly worried about game balance here either. (That said, it would be good to create art that might be useful for real rulesets later, if we're going to the effort.)

The main constraints are

Must be available for all supplied tilesets by release time (so might need multiple artists to agree). (There will be 8 tilesets in 2.6, but usually a given item can be drawn fewer times. For instance units need drawing only in Cimpletoon, Amplio, and Trident styles.)

Must be known to be under a suitable licence (GPL2-compatible). (So I haven't felt able to raid GM1530's extensive tile sets like this one as I don't know the owner/licence and suspect it's not suitable.)

Must fit existing engine capabilities; this thread isn't for discussion of changes to the engine.

2.6 will introduce the concept of "animals", but so far no ruleset enables them.

Here's my understanding of animal behaviour (based on reading the code) -- cazfi (as originator of the concept) may be able to explain philosophy and future direction and what he had in mind.

One Animal Kingdom AI "barbarian" player is created at game start to manage the animals (we already have flag for this); players don't interact much with this AI

Each terrain type has just one characteristic animal (or none); so for any given terrain there's one kind of animal that'll spawn there, but a given animal can call multiple terrains home (so if both Hills and Mountains have animal=Mountain Lion, then wild lions will roam inside any contiguous region of uplands, but will never step/attack outside)

Animal movement restriction to terrain is a property of the owner, not the unit; so if an animal can be captured it can then be moved anywhere, subject to the usual rules

Map is randomly populated with animal units according to map size and terrain availability at game start

Animals do not respawn, and once they're all gone, they're gone (as is the animal player)

The obvious example is top predators -- lions, bears, etc. It's possible to think of suitable examples for most standard terrain types. They really do have to be quite large and fearsome to make narrative sense at Freeciv's scale though (so probably not alligators in swamps). Perhaps they could also represent multiple animals (e.g. pack of wolves). I'm not sure ocean/lake attackers make sense (unless you want a Kraken).The previous thread concentrated on this, but I'm hoping for some art more in keeping with existing tileset styles. (The bear might be usable for Amplio.)

A slight variation might be a swarm of locusts that cannot attack but reduces food yield of the tile it's on.

Another possibility is animals that can be captured and tamed (mobile hut-like map bonuses). For instance, a herd of horses that can be captured* and converted** to some Horsemen-like unit (using existing graphics); similarly elephants. (But there's going to be a lot of luck involved in whether you meet animals, so probably this should not create a high long-term strategic advantage.)

* (Ability for one unit to capture another has existed for a long time, but is also not used in many rulesets.)** See below.

Unit conversion

The game's long had the ability for one unit to convert to another type (since 2.3, although it changed substantially in 2.5), but it's rarely if ever used in rulesets.

A given unit type can be converted on demand to at most one other type (but any number of unit types can be the source for one target unit). This always takes at least one full turn, ruleset-defined. The target type may be able to convert back or not, as the ruleset author desires.

One obvious use is to convert units between a mobile and immobile but more useful form (the latter having no movement points).

One such conversion could be some sort of siege engine or bombard, with a high attack value when stationary but requiring time to assemble and dismantle, and having no attack value when mobile. It might be fairly easy to derive fixed and mobile forms from existing Catapult (etc) graphics.

Another is a one-way conversion to a stationary form of unit. This could be used for instance for a work camp or mine that funnels special resources back to its home city; a gun emplacement; etc; that is, something that can never be moved once deployed, only disbanded, destroyed, or captured. Remember a given mobile unit can only convert to one stationary one, so probably can't use Workers / Engineers as the mobile form in a real ruleset (may be OK in an experimental one).See also patch #6479 for some thoughts on limitations of this concept.

(A third use mentioned above, not requiring immobile units, is to tame wild animals.)

JTN wrote:Must be known to be under a suitable licence (GPL2-compatible). (So I haven't felt able to raid GM1530's extensive tile sets like this one as I don't know the owner/licence and suspect it's not suitable.)

It's impossible to say. Why? I tried to contact the author 3 times during 6 years in 2007, 2010 and 2013. Result? No one reply. Anyway you can remove the link, error 404

If you are looking for working 2.5 examples exploring some not yet used features without new artwork, I tested some stuff: Unit conversion settler to worker, as expected, and quite useful when I try to get rid of captured towns without any shift-B target for the "help build" business.

New free tech A-CIVILIZATION (using the freeciv icon as artwork) to visualize A-NONE in the research tree, i.e., permit settlers, warriors, capitalzation, root req for everything else in the first column, and because some AIs hated it make sure that only masonry can be researched (requiring A_CIVILIZATION). No palace (and no capital) without masonry, two classic/experimental effects depending on the existence of a palace for their "distance from capital" calculations had to be fixed for this idea.

New tech A-CRYPTOGRAPHY requiring Espionage + Theology (approximating "snake oil"), undoes the negative Communism effect on cathedrals, enables Cinema, where Cinema obsoletes Colosseum (same idea as Barracks III obsoleting Barracks II, or II obsoleting I otherwise, works like a charme, work lists are automatically upgraded to Cinema when available.) But no new artwork, I just used Colosseum also for Cinema.

Rather obscure, new base marina for ships on land, requiring an existing fortress. First I wanted fortress + airbase, but that wasn't intuitive, the normal "build fortress" F can add a marina to an existing fortress -- requires adjacent lake or ocean, ships cannot fly Artwork: Recycled buoy, the hidden purpose is of course cheating, get some kind of marina-channel from an ocean to a city to another ocean without terraforming. The secret purpose of buoys is to steal fish or whales from your AI-allies and AI-enemies alike, but I digress.

If we're going to have only one animal, I really want it to be big cats or wolves. I don't think a world where Man's greatest fear is the crocodile is plausible. (But we can have those as secondary animals if we scrape up an A-list apex predator.)

Here I'll keep notes on what art I've been able to find. We need units in three styles: Trident (civ1-ish) and Amplio (civ2-ish), and Cimpletoon (3D -- I can render models if necessary).

(I've had a good look for civ2 units in particular; there's loads of good stuff out there from the turn of the century, but very few wild animals, and the licensing position is usually very unclear. As a reminder, anything we ship has to be squeaky-clean to redistribute under GPL2.)

JTN wrote:I'm getting quite desperate to find some kind of animal for 2.6.

What exactly do you expect, is it in the direction of some 64x32 RGBA PNG with a transparent background? I stumbled over a nice hyena with this thread in mind:

The related http://opengameart.org/content/hyena thread explains the issues with creating "free" art at all, and with finding it. As far as I could see it no civ2 contribution has a decent license in the direction of PD/CC0/CC-BY, or CC-BY-SA (not yet directly GPL-compatible as long as Freeciv insists on GPL also for art), or obviously unusable CC-NC- and CC-ND-variations (i.e., good enough for art in a modpack, but not in Freeciv proper, the wiki, or even this forum.)

I'm holding out for art that matches the style of the existing units in the relevant tilesets, e.g. an Amplio lion that doesn't look out of place next to an Amplio Legion. If I were to relax my standards to any image that can be squashed into the sprite size, I expect I'd have no trouble finding images.

I think I've been underrating the hippo's aggressiveness and the respect it had from ancient civilisations, so I've added it to the B-list. (A minor game engine change would be required to restrict it to rivers though.)

Probably for the sandbox ruleset it would be OK to say that you only get good sprites with one supplied tileset, say Hexemplio; that would allow me to mine GriffonSpade's excellent additions to the Ampliohex tileset (not that that helps with animals, but it does give a variety of terrain, resources etc).

Indeed. Would have to contact the listed authors in all cases, I think, and even then I'm not sure I'd trust the answer. I'm guessing a lot of this material comes from a simpler time of unrestricted sharing / adapting from commercial games without regard for licensing. Which is a shame, because there's loads of good stuff there.

Not found on Commons:Bad sources, that's good. They have "our" bears: 1, 2, 3, okay, but apparently nothing that's obviously better (for a bear). The main trick is the down-scaling and converting any background pixels to fully transparent.

I tried imageworsener for the scaling, the results "worked for me" (=needs review by somebody with younger eyes). There's a category:Animal kingdom on the Wiki for "work in progress". The main issue is the license, how much would I trust pd4pic? As far as I can throw them.